1. What Is WEEK(NOW() + INTERVAL n WEEK)?

This SQL function calculates the week number for a date that is 'n' weeks from the current date. It combines the WEEK() function with date arithmetic using NOW() and INTERVAL.

2. How Does This SQL Function Work?

The function consists of three parts:

Where:

• \( WEEK() \) — Returns the week number for a date
• \( NOW() \) — Returns the current date and time
• \( INTERVAL n WEEK \) — Adds 'n' weeks to the current date

Explanation: The expression calculates the week number for a date that is 'n' weeks in the future from the current date.

3. Practical Applications

Details: This is commonly used in SQL queries for scheduling, reporting, and analyzing data by week intervals. Useful for forecasting, trend analysis, and weekly aggregation.

4. Using The Calculator

Tips: Enter the number of weeks you want to add to the current date. The calculator will generate the appropriate SQL expression.

5. Frequently Asked Questions (FAQ)

Q1: What SQL databases support this function?
A: MySQL and MariaDB support this syntax. Other databases may have slightly different implementations.

Q2: How does WEEK() handle year boundaries?
A: WEEK() typically follows the database's week numbering rules, which may vary by system variable settings.

Q3: Can I calculate past weeks with this?
A: Yes, use negative values for 'n' to calculate weeks in the past.

Q4: What's the difference between WEEK() and WEEKOFYEAR()?
A: WEEK() can use different modes for week numbering, while WEEKOFYEAR() always uses mode 3 (ISO week numbers).

Q5: How precise is NOW() in this calculation?
A: NOW() includes the current time, but WEEK() only considers the date portion.